..However, to date, no placebo-controlled trial has assessed sildenafil's effectiveness for treating ED in PTSD patients. The goal of the present study was to address this question using a double-blind placebo controlled crossover design...

An open-label pilot study to evaluate the efficacy of sildenafil citrate in middle-aged men with late-onset dysthymia

..Sildenafil citrate might have an antidepressant effect on late onset DD, that is not attributable to improvement in erectile function. Possible explanations for this effect are offered. Larger placebo controlled studies are warranted...